The UK Foreign Office has advised against all but essential travel to the Chinese city of Wuhan after a new virus killed 17 and infected hundreds.
The deadly coronavirus has also infected more than 500 people.
Screening is in place at major US airports, while Britain’s transport secretary said a separate area was being set up at London Heathrow to monitor arrivals from affected areas and deal with anyone who’s sick.
The first case in the US was identified this week, while others have been diagnosed in Thailand, South Korea, Japan, Hong Kong and Taiwan.
All of them had been to Wuhan – the Chinese city with an 11 million population where the virus is believed to have started – with illegally trafficked animals at a market being named as the likely source.
Symptoms of the virus include fever, coughing and difficulty breathing.
More serious cases could lead to potentially deadly conditions such as pneumonia and kidney failure.
More from China
Concerns are growing as hundreds of millions of people in China prepare to travel for the Lunar New Year holiday, which starts on Saturday.
Image: Chinese police officers wear protective masks as they patrol at Beijing station
Image: A man is taken to hospital in Hong Kong as it detects its first cases of the virus
Sales of surgical masks have increased and some people are cancelling trips and avoiding public places as cases of the virus have been diagnosed in Beijing and Shanghai.
Taiwan has joined Australia in telling its citizens to avoid Wuhan, while North Korea has banned foreign tourists – most of whom are Chinese.
Image: Singapore is one of the countries scanning people for signs of fever as they land
Singapore is also among the countries that have started screening all passengers arriving on flights from China – with heat-detecting guns scanning people for signs of fever.
In the UK, health body Public Health England (PHE) has revised the coronavirus risk from “very low” to “low”.
Coronaviruses are a large family of viruses ranging from the common cold to severe diseases such as SARS – which killed nearly 800 people during the 2002-03 outbreak.
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When a new strain emerges that has not yet been identified, as with the current outbreak, it becomes known as a novel coronavirus (nCoV).
Chinese state media say the latest strain is different from those identified in the past, but have confirmed it can be passed from person to person.
All coronaviruses are also zoonotic, meaning they are transmitted between animals and people.
There are no reliable vaccines. The best someone can do is take medicines and treatments for specific symptoms.
Source : Sky News